crashed wireless phone.wav

This is another example of a malfunction from my wireless phone.
A previous example was here:
http://freesound.org/people/AlienXXX/sounds/345954/

This time one of the handsets froze and kept displaying the message "power cut".
The keyboard on that handset was unresponsive and the handset would also not receive any calls.

The battery is built in. There is no off switch on the handsets. So the only option to try to resolve a crash is to remove that handset from the stand and wait for the battery to run out.

The LCD display light on the handset kept permanently on, but even then the battery takes at least a couple of says to run out.
A few minutes ago I noticed the handset was making this sound (kind of a fizzing/crackling sound). IT is quite faint, so I had to take the recorder to my room and place it under a pillow along with the handset to try to isolate it from other noise and record the sound.

Recorded on a Sony PCM-D50 with the input volume set to 5.